Brush-holder.



S. H. MORTENSEN.

BRUSH HOLDER.

APPLICATION FILED APR.15, 1909.

P atented Feb.13,1912.

2 SHEETS-SHEET 1.

S. H. MORTENSEN.

BRUSH HOLDER.

APPLICATION FILED APR.15, 1909.

Patented Feb. 13, 1912.

2 SHEETS-SHEET 2.

//////////IIIII/MI////II/////III//I1I V I W Li am m CH. WWW @s/Za 5 45 4UNITED STATES PATENT OFFICE.

SGREN H. MORTENSEN, OE MILWAUKEE, WISCONSIN, ASSIGNOR TOALLIS-CI-IALMERS COMPANY, A CORPORATION OF NEW JERSEY.

BRUSH-HOLDER.

Specification of Letters Itatent.

Patented Feb. 13, 1912.

To all whom it may concern:

Be it known that I, SoREN I-I. MORTENSEN, a subject of the King ofDenmark, residing at Milwaukee, in the county of Milwaukee and State ofW'isconsin have invented certain new and useful Improvements inBrush-Holders, of which the following is a full, clear, and exactspecification.

This invention relates to current collecting apparatus, including brushholders and brush holder supports designed particularly for high speedmachines such as direct current turbo-generators.

One of the objects of the invention is to provide an effective brushholder having brushes and followers or pressure devices possessing lowmoments of inertia and high natural periods of vibration so that thebrushes will follow very closely the surface of the commutator andsparking will be reduced to a minimum.

A further object is to provide a rigid suporting means for the brushholders which will hold the latter firmly in position and preventvibration.

The invention may be briefly summarized as consisting in certain noveldetails of con struction and combinations and arrangements of partswhich will be described in the specification and set forth in theappended claims.

Reference is had to the accompanying sheets of drawings, in which-Figure 1 is a side elevation of the current collecting apparatusincluding the brush holders and supporting means therefor; Fig. 2 is atransverse section taken through the brush ring and yoke andsubstantially along the lines 2-2 of Fig. 1, looking in the directionindicated by the arrows, a portion of the field yoke being shown inelevation; Fig. 3 is an enlarged side view of one of the brush holdersprovided with brushes; Fig. 4 is another view of the same looking towardthe end of the holder; Fig. 5 is a section taken through the holdersubstantially along the line 55 of Fig. 3, looking in the directionindicated by the arrow; Fig. -6 is a fragmentary View substantiallyalong the line 6-6 of Fig. 1, looking in the direction indicated by thearrow; and Fig. 7 is an enlarged view of one of the followers orpressure devices employed in connection with each of the brushes.

Referring now to the figures of the drawing wherein I have shown thepreferred embodiment of my invention, 10 represents a portion of thefield frame or yoke of a high speed machine, and 11 the commutator whichis provided with segments surrounded and held in position by spacedretaining rings 12. The brush holders are in this case supportedindependently of the main frame or yoke of the machine, and for thispurpose I have provided as a part of the brush rigging or collectingapparatus, a separate brush yoke 13, which in side elevation is quitesimilar to the field frame or yoke of the machine and which is supportedand secured in position by feet 13 independently of the field yoke. Thebrush yoke which is divided into two parts for convenience in assemblingand handling carries an inner ring 14: which is designed to be adjustedcircumferentially relative to the yoke by means of a'handle 15 securedto the ring and extending through a slot 16 in the yoke. The ring may besecured in any desired adjusted position by means of one or more setscrews 17 extending through the yoke and engaging a V-shaped groove inthe periphery of the ring. Extending inwardly from the ring 1 1 andintegral therewith are a number of arms 18 in this case two in number,and arranged diametrically opposite each other, each of the arms 18supporting a bracket 19 to which brush holders, which will be describedpresently, are secured. Each bracket has a pair of arms 20 which extendoutwardly on opposite sides of the corresponding arm 18 of the ring andare secured thereto by a transverse bolt 21, the arms of the bracketbeing separated and insulated from the arm of the ring by a U-shapedsheet of insulation 22., shown clearly in Fig. 6. Each of these brackets19 is also provided with an inner portion 23 which extendslongitudinally of the commutator and to which a number of brush holders24 are bolted, each bracket in this case being designed to have boltedthereto, three brush holders. As will be seen in Fig. 2, the portions 23of the brackets to which the brush holders are secured are quite closeto the surface of the commutator and each of said portions is providedintermediate its ends with a notch 25 in which the middle retaining ring12 of the commutator rotates,

the brush holders being designed to be secured to each bracket onopposite sides of the notch.

The brush holders 24 are each preferably cast in one integral piece frommetal of good conducting material such as brass, and each holder in thiscase includes a box-like brush receiving or supporting portion 26, alsoa portion 27 which is bolted to the portion 23 of the bracket and whichis connected to the brush receiving portion 26 by a pair of arms 28, andan outer portion 29 which extends over the portion 26 and which carriessleeves forming part of the follower or pressure mechanism, the portion29 being connected to the inner portions 26 and 27 by means of a pair ofarms 30 and 31 which extend inwardly from opposite corners of theportion 29.

In order that the brushes may have small moments of inertia and at thesame time large current carrying capacity when taken collectively, eachholder is provided with a large number of rather small brushes 32arranged in two rows, the brushes of one row being inclined relative tothe brushes of the other row, so that the inner faces or ends of thebrushes will be adjacent. To accom modate these brushes the portion 26of the holder is divided by longitudinal and trans verse partitions 26and 26 into a number of sockets, one for each brush. The outer portion29 of each holder is provided with a number of threaded sockets equal innumber to the brush sockets in the portion 26 of the holder, andhavingthe same relative arrangement and being axially in line with the socketsfor the brushes. Screwed into these threaded sockets are sleeves 33,each provided with an outer knurled head 34, a threaded portion 35, ashoulder 36, and a reduced portion 37 which extends inwardly beyond theportion 29 of the brush holder. The brushes are held yieldingly upon thesurface of the commutator by means of rods or plungers 38 and coilsprings 39 which surround the rods,'each rod having at one end anenlarged portion 40 provided with a rounded nose or tip 41 which isfouned of insulating material and bears upon the outer end of the brush.The coil spring 39 which surrounds each rod bears against the enlargedportion 40 of the rod and the shoulder 36 of the sleeve, the tension ofthe spring depending, of course, upon the adjusted position of thesleeve 33. In order that the sleeves may be locked in any desiredadjusted positions and may be readily released for adjustment, eachsleeve is provided with longitudinal grooves or slots 43, which, in thiscase are located diametrically opposite each other, and the portion 29of the holder is provided between the sleeves with locking springs ttwhich are secured by means of screws 45 between the sleeves,

one being provided between each pair of sleeves and having bowedportions which project in the slots of the sleeves so as to normallylock the same against movement, and free end portions which formconvenient means for withdrawing the springs from the slots. It will beseen that a follower or pressure device ofthe construction here shownhas very little moment of inertia compared with other pressure devices,such as those including pivoted arms which bear upon the brushes, andhence will cause the brushes to follow closely any irregularities on thesurface of the commutator.

The brushes of one row of each holder are connected by pig-tails 46 tothe portion 27 of the holder and the brushes of the other row areconnected by pig-tails 47 to the outer portion 29 of the holder.Inasmuch as the rods 38 are provided at their inner ends with insulatingtips which bear upon the brushes, no current can pass through thesprings so as to anneal or weaken the same, but will be carried by thepig-tails to the holders or will pass directly from the brushes to theholders.

I do not desire to be confined to the exact details shown and described,but aim in my claims to cover all modifications which do not involve adeparture from the spirit and scope of my invention.

l Vhat I claim as new and desire to secure by Letters Patent is:

1. In combination, a brush rigging for a dynamo-electric machine,comprising a yoke independent of the field yoke of the machine, a ringcarried by said yoke, said ring having inwardly extending arms, andbrackets secured to said arms and insulated therefrom, said bracketshaving brush holders secured thereto.

2. In combination, in a dynamo-electric machine, a main frame or yoke, abrush rigging comprising a brush yoke independent of the main yoke, aring supported by said brush yoke, said ring having inwardly projectingarms, a plurality of brush holders, and brackets to which said holdersare secured, said brackets having arms whichproject outwardly onopposite sides of the arms on the rings and are rigidly secured thereto.

3. A field frame, a brush yoke supported independently of the fiel'dframe, a ring adjustably mounted on said yoke, said ring having inwardlyprojecting arms, a plurality of brush holders, and brackets to whichsaid brush holders are bolted, said brackets each having a pair of armsprojecting outwardly on opposite sides of one of said arms on the ring,U-shaped sheets of insulation separating the arms of the bracket fromthe arms of the ring, and bolts passing through said arms and securingthe brackets to the ring.

4. In combination, a brush rigging for a dynamo-electric machine,comprising a yoke independent of the field yoke of the machine, a ringrotatable within said yoke, a brush holder mounted on said ring andcomprising a brush-receiving portion, an outer brush follower supportingportion, a pair of inwardly projecting arms connecting said followersupporting portion to the brush-receiving portion, said brush-receivingportion having a plurality of brushes, said follower supporting portionhaving sockets arranged in alinement with the brushes, threaded sleevesin said sockets, and pressure springs between said sleeves and brushes.

5. In combination, a brush rigging for a dynamo-electric machine,comprising a yoke independent of the field yoke of the machine, a ringrotatable within said yoke, a brush holder mounted on said ring andhaving a frame or body portion with a brush-receiving portion,partitions dividing the same into a number of brush sockets arranged inadjacent rows, a follower supporting portion extending over thebrushreceiving portion and connected thereto, brushes in said sockets,said follower supporting portion having threaded socket-s, sleevesmounted in said threaded sockets and having an arrangement correspondingto the arrangement of the brushes and be ing in alinement therewith, andcoil springs arranged in the brushes and sleeves.

6. In combination, a brush rigging for a dynamo-electric machine,comprising a yoke independent of the field yoke, a ring movable on saidyoke, a brush holder mounted on said ring and comprising a frame or bodyhaving a brush receiving portion, longitudinal and transverse partitionsdividing the same into brush receiving sockets, brushes in said sockets,a follower supporting portion extending over the brush receiving portionand provided with threaded sockets having an arrangement correspondingto the arrangement of the brush receiving sockets, and being inalinement therewith, sleeves in said threaded sockets, rods extendingthrough said sleeves and having near their inner ends shoulderedportions insulated from the receiving portion, longitudinal transversepartitions dividing the same into brush sockets, brushes in saidsockets, a follower supporting portion extending over the brushreceiving portion and provided with threaded sockets having anarrangement corresponding to the arrangement of the brush receivingsockets, and being in alinement therewith, sleeves in said threadedsockets, rods extending through said sleeves and having near their innerends shouldered portions insulated from the brushes, coil springssurrounding the rods and bearing against the shouldered portions of thelatter and the sleeves, and means for locking the sleeves againstmovement;

8. In combination, a brush holder comprising a frame or body having abrush receiving portion, partitions dividing the same into a pluralityof sockets arranged in two rows, brushes in said sockets, a followersupporting portion connected to the brush receiving portion andextending over the latter, said follower supporting portion beingprovided with threaded sockets having the same arrangement as, and beingin alinement with the brush receiving sockets, adjustable sleeves insaid threaded sockets, rods extending through said sleeves and havinginsulating portions at their inner ends adapted to bear against thebrushes, said sleeves and rods having shouldered portions, and coilsprings surrounding the rods and engaging the shouldered portions of thesleeves and rods respectively, said sleeves having longitudinal slotsand looking springs arranged between the slots and adapted to engagesaid slots so as to hold the sleeves against accidental movement.

In testimony whereof I affix my signature, in the presence of twowitnesses.

soREN H. MORTENSEN.

Witnesses:

II. C. CAsE, CHAS. L. BYRON.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

